I am the proud owner of a 2004 MG ZT 260 SE. The general build quality is great. The handling, ride and braking are superb. The performance from the Ford V8 puts a big smile on my old face. My problem is tyres. I bought the car with 20,000 on the clock and put a set of Pirellis on at 25,000 six months ago. The car has just had a service at 30,000 and to my surprise the mechanic reports that the two rear tyres need replacing. I know that Pirellis are on the soft side and that the recommended tyre pressures (36 rear 34 front) are correct. I do not drive at excessive speed or excessive mileage except for a little bit of wellie (for ego purposes) on a clear road now and again. So 5,000 every six months. What could it be?